Field of the Invention
The invention relates to a tubular blanket washing system which is offline, i.e. not part of a printing press.
Offset lithographic web printing presses have printing units containing several printing cylinders rotating between side frames. The cylinders include a print cylinder carrying a print form having an image thereon and a blanket cylinder carrying a blanket tube. The image is transferred from the print form to the blanket tube and from the blanket tube to the web.
Vertical and horizontal web offset presses having gapless blanket tubes may include on-press blanket washers. Such washers are typically integrated into the structure of the press. However, end users of web offset presses often do not purchase on-press blanket washers and therefore manual washing of the blanket tubes must be performed. This results in down-time for the press and accordingly must be performed quickly leaving little time for inspection. The tubes do not have time to "rest" and be rejuvenated and the use of chemicals on the press is required.
In addition, some presses have limited access for washing the blanket tubes and some washing chemicals are not recommended for use on the press. In such cases, the blanket tubes must be removed for cleaning. U.S. Pat. No. 5,813,336 discloses a printing unit from which print forms and blanket tubes can be removed through an opening in a side frame.